@AvirahDeArah
I can help you out with that first pasuk you’re struggling with there. Rambam also quotes it in Hilchos Avodim 9:8..
“Cruelty and arrogance are only found with idol worshippers, but the descendants of Avraham Avinu who Hashem granted upon them the goodness of the Torah and commanded them with the laws and statutes, they are righteous and merciful on all. Similarly, with regards to the attributes of Hashem that we are commanded to emulate, it is written “His mercies be upon all his works.”
Pretty clear that Rambam views this ‘being merciful to everyone’ business as a pretty big deal…wouldn’t you say?
I can’t see any indication in the Rambam that the first pasuk is referring to the first part of the halacha, and the second to the last (Rambam could easily have structured it like that). The simple reading seems to be that both pesukim are pertinent to the whole halacha.
Have you ever “learned up” a rambam before?